Convert audio to WAV 8 bit

[Eugeny]

Hello, while I am using VLC for quite a long time, now I have a task to perform automated operations on the media files, and I discovered that VLC has very very powerful command line interface!

I have figured out how to slice video into frames using scene filter.

But I have problems converting audio. Source is (let's say) MP4 44100 stereo 16 bit, I need output as WAV 22050 mono 8bit. I use transcoding, tried s8 codec, it creates file of correct size, but it sounds like overloaded, tried u8 codec, it creates file of correct size which does not open at all.

VLC 2.2.2 Weathermwax Windows 7 x86

Please help me with audio. Thank you!

I found issue with U8. It writes 0 into field audioFormat, while this field should be 1. After I changed it to 1 in the file, file plays properly.
Please fix it, or tell me what I do wrongly.

S8 is having correct 1 in this field.
Some more information. V1.1.9 does not convert at all. V2.0.8 is having same U8 issue, thus it is historical problem which was not found yet.

Also, I can use "File audio output" (--audiofile) which works properly, but there's no samplerate argument to change it from default 44100 to 22050.

[mederi]

Please report s8, u8 issues at https://trac.videolan.org/vlc

If you want help with CLI options, then use streaming wizard in VLC GUI (Media > Stream...) where you will get the generated stream output string in the last step.

Code: Select all

:sout=#transcode{vcodec=none,acodec=u8,channels=2,samplerate=22500}:standard{access=file,mux=wav,dst="H:\u8.wav"}

--sout-transcode-samplerate=<integer [0 .. 48000]>
Sample rate of the transcoded audio stream
(11250, 22500, 44100 or 48000).
Sample rate of the transcoded audio stream (11250, 22500, 44100 or
48000).

[Eugeny]

Code: Select all

11250, 22500, 44100

I assume 11250 and 22500 are a typos. Standard freqs are 11025 and 22050.